Particle acceleration by slow modes in strong compressible MHD turbulence, with application to solar flares

Abstract

Energetic particles that undergo strong pitch-angle scattering and diffuse through a plasma containing strong compressible MHD turbulence undergo diffusion in momentum space with diffusion coefficient Dp. In this paper, the contribution of slow modes to Dp is calculated assuming the rms turbulent velocity is of order the Alfven speed. The energy spectrum of accelerated particles is derived assuming slow modes make the dominant contribution to Dp, taking into account Coulomb losses and particle escape from the acceleration region with an energy-independent escape time. The results are applied to solar flares.

arXiv comment19 pages, 3 figures, accepted for publication in ApJ

References in corpus (7)

• The Anisotropy of MHD Alfvénic Turbulence
• Simulations of Incompressible MHD Turbulence
• MHD Turbulence Revisited
• Compressible Sub-Alfvenic MHD turbulence in Low-beta Plasmas
• Compressible MHD Turbulence in Interstellar Plasmas
• Scattering of Cosmic Rays by Magnetohydrodynamic Interstellar Turbulence
• Scattering of energetic particles by anisotropic magnetohydrodynamic turbulence with a Goldreich-Sridhar power spectrum

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